Antipoisoning Nickel-Carbon Electrocatalyst for Practical Electrochemical CO2 Reduction to CO

The feasibility of utilizing electrochemical reduction of CO2 (CO2RR) to close the global carbon cycle is hindered by the absence of practical electrocatalysts that can be adopted in large CO2 emitting sources with impurities. To address this, we use density functional theory (DFT) calculations to design a strategy to develop Ni coordinated graphitic carbon shells (referred as Ni@NC-900) catalyst. This strategy not only prolongs stability and endows antipoisoning properties of the catalyst but also reforms the electronic structure of the outer graphitic carbon shell to make it active for CO2RR. As a result, Ni@ NC-900 demonstrates a high conversion of CO2 to CO with a Faradaic efficiency (FECO) of 96% and a partial current density for CO (jCO) of ∼−17 mA cm−2 at an applied potential of −1 V versus reversible hydrogen electrode (RHE). This activity can be further scaled up to attain a jCO of ∼30 mA cm−2 for 18 h at a cell voltage of 2.6 V in a high-throughput continuous gas diffusion electrode (GDE) system. In addition to exhibiting high activity and stability, Ni@NC-900 displays exceptional tolerance toward impurities (from SOx, NOx, CN−), highlighting the suitability of these rationally designed catalysts for large-scale application in fossil-fuel based power plantsThe work was supported by the Australian Research Council (ARC) under the Laurate Fellowship Scheme FL-140100081, Discovery Early Career Researcher Award DE170100375 and funding from the UNSW Digital Grid Futures Institute, UNSW Sydney under a crossdisciplinary fund scheme